Cytotoxicity and genotoxicity of oyster shell: A biocompatibility evaluation

Xiulan LI; Chengzhi GAO

ABSTRACT

BACKGROUND:

Oyster shell has been recently reported as a new root canal filling material; therefore, it needs primary biological evaluation, i.e., cytotoxicity test and genotoxicity test, before clinical application.

OBJECTIVE:

To evaluate cytotoxicity and genotoxicity of oyster shell powder. DESIGN, TIME AND

SETTING:

A contrast observational study was performed at the Materials Laboratory, School of Stomatology of Peking University from April to July 2008. MATERIALS Oyster shell powder was provided by Institute of Oceanology, Chinese Academy of Sciences; L929 cell strain and Salmonella typhimurium TA97, TA98, TA100, and TA102 were provided by the National Institute for the Control of Pharmaceutical and Biological Products.

METHODS:

Oyster shell diffusion was prepared based on the times of 0.5, 1, and 2. According to the standards of biological evaluation of dental materials, the cytotoxity and genotoxicity of oyster shell were evaluated with molecule filter test and Ames test. MAIN OUTCOME

MEASURES:

Fading area of the film induced by succinic dehydrogenase and amount of spontaneous revertants.

RESULTS:

After 2 hours, the results indicated that fading area of the film in the experimental group was the same as negative control, i.e., fading was not found in the film, and cytotoxicity was grade 0. After 24 hours, diameter of non-stained film was 1.0-2.0 mm, fading area was 1-3 mm2, and cytotoxicity was grade 1, suggesting that the material had light cytotoxity that was still qualified. The spontaneous revertant test indicated that the mutagenicity of experimental groups was no more than 2 times of the control groups, suggesting there was no dose-dependence.

CONCLUSION:

Oyster shell powder has no cytotoxicity and genotoxicity on the organism.